[PATCH v2 0/2] PCI: qcom: Add support for SDM845 PCIe

[PATCH v2 0/2] PCI: qcom: Add support for SDM845 PCIe

[Bjorn Andersson]

This second iteration of the patch series fixes review comments on v1 and has
been tested with both PCIe controllers found on the Qualcomm SDM845.

Bjorn Andersson (2):
  dt-bindings: PCI: qcom: Add support for SDM845 PCIe
  PCI: qcom: Add support for SDM845 PCIe controller

 .../devicetree/bindings/pci/qcom,pcie.txt     |  19 +++
 drivers/pci/controller/dwc/pcie-qcom.c        | 152 ++++++++++++++++++
 2 files changed, 171 insertions(+)

-- 
2.23.0

[PATCH v2 1/2] dt-bindings: PCI: qcom: Add support for SDM845 PCIe

[Bjorn Andersson]

Add compatible and necessary clocks and resets definitions for the
SDM845 PCIe controller.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---

Changes since v1:
- Split out binding in separate patch

 .../devicetree/bindings/pci/qcom,pcie.txt     | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/Documentation/devicetree/bindings/pci/qcom,pcie.txt b/Documentation/devicetree/bindings/pci/qcom,pcie.txt
index ada80b01bf0c..981b4de12807 100644
--- a/Documentation/devicetree/bindings/pci/qcom,pcie.txt
+++ b/Documentation/devicetree/bindings/pci/qcom,pcie.txt
@@ -11,6 +11,7 @@
 			- "qcom,pcie-ipq4019" for ipq4019
 			- "qcom,pcie-ipq8074" for ipq8074
 			- "qcom,pcie-qcs404" for qcs404
+			- "qcom,pcie-sdm845" for sdm845
 
 - reg:
 	Usage: required
@@ -126,6 +127,18 @@
 			- "master_bus"	AXI Master clock
 			- "slave_bus"	AXI Slave clock
 
+-clock-names:
+	Usage: required for sdm845
+	Value type: <stringlist>
+	Definition: Should contain the following entries
+			- "aux"		Auxiliary clock
+			- "cfg"		Configuration clock
+			- "bus_master"	Master AXI clock
+			- "bus_slave"	Slave AXI clock
+			- "slave_q2a"	Slave Q2A clock
+			- "tbu"		PCIe TBU clock
+			- "pipe"	PIPE clock
+
 - resets:
 	Usage: required
 	Value type: <prop-encoded-array>
@@ -188,6 +201,12 @@
 			- "pwr"			PWR reset
 			- "ahb"			AHB reset
 
+- reset-names:
+	Usage: required for sdm845
+	Value type: <stringlist>
+	Definition: Should contain the following entries
+			- "pci"			PCIe core reset
+
 - power-domains:
 	Usage: required for apq8084 and msm8996/apq8096
 	Value type: <prop-encoded-array>
-- 
2.23.0

Re: [PATCH v2 1/2] dt-bindings: PCI: qcom: Add support for SDM845 PCIe

[Rob Herring]

On Fri,  1 Nov 2019 17:27:20 -0700, Bjorn Andersson wrote:
> Add compatible and necessary clocks and resets definitions for the
> SDM845 PCIe controller.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
> 
> Changes since v1:
> - Split out binding in separate patch
> 
>  .../devicetree/bindings/pci/qcom,pcie.txt     | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 

Reviewed-by: Rob Herring <robh@kernel.org>

[PATCH v2 2/2] PCI: qcom: Add support for SDM845 PCIe controller

[Bjorn Andersson]

The SDM845 has one Gen2 and one Gen3 controller, add support for these.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
---

Changes since v1:
- Style changes requested by Stan
- Tested with second PCIe controller as well

 drivers/pci/controller/dwc/pcie-qcom.c | 152 +++++++++++++++++++++++++
 1 file changed, 152 insertions(+)

diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
index 7e581748ee9f..35f4980480bb 100644
--- a/drivers/pci/controller/dwc/pcie-qcom.c
+++ b/drivers/pci/controller/dwc/pcie-qcom.c
@@ -54,6 +54,7 @@
 #define PCIE20_PARF_LTSSM			0x1B0
 #define PCIE20_PARF_SID_OFFSET			0x234
 #define PCIE20_PARF_BDF_TRANSLATE_CFG		0x24C
+#define PCIE20_PARF_DEVICE_TYPE			0x1000
 
 #define PCIE20_ELBI_SYS_CTRL			0x04
 #define PCIE20_ELBI_SYS_CTRL_LT_ENABLE		BIT(0)
@@ -80,6 +81,8 @@
 #define PCIE20_v3_PARF_SLV_ADDR_SPACE_SIZE	0x358
 #define SLV_ADDR_SPACE_SZ			0x10000000
 
+#define DEVICE_TYPE_RC				0x4
+
 #define QCOM_PCIE_2_1_0_MAX_SUPPLY	3
 struct qcom_pcie_resources_2_1_0 {
 	struct clk *iface_clk;
@@ -139,12 +142,20 @@ struct qcom_pcie_resources_2_3_3 {
 	struct reset_control *rst[7];
 };
 
+struct qcom_pcie_resources_2_7_0 {
+	struct clk_bulk_data clks[6];
+	struct regulator_bulk_data supplies[2];
+	struct reset_control *pci_reset;
+	struct clk *pipe_clk;
+};
+
 union qcom_pcie_resources {
 	struct qcom_pcie_resources_1_0_0 v1_0_0;
 	struct qcom_pcie_resources_2_1_0 v2_1_0;
 	struct qcom_pcie_resources_2_3_2 v2_3_2;
 	struct qcom_pcie_resources_2_3_3 v2_3_3;
 	struct qcom_pcie_resources_2_4_0 v2_4_0;
+	struct qcom_pcie_resources_2_7_0 v2_7_0;
 };
 
 struct qcom_pcie;
@@ -1068,6 +1079,136 @@ static int qcom_pcie_init_2_3_3(struct qcom_pcie *pcie)
 	return ret;
 }
 
+static int qcom_pcie_get_resources_2_7_0(struct qcom_pcie *pcie)
+{
+	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+	struct dw_pcie *pci = pcie->pci;
+	struct device *dev = pci->dev;
+	int ret;
+
+	res->pci_reset = devm_reset_control_get_exclusive(dev, "pci");
+	if (IS_ERR(res->pci_reset))
+		return PTR_ERR(res->pci_reset);
+
+	res->supplies[0].supply = "vdda";
+	res->supplies[1].supply = "vddpe-3v3";
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(res->supplies),
+				      res->supplies);
+	if (ret)
+		return ret;
+
+	res->clks[0].id = "aux";
+	res->clks[1].id = "cfg";
+	res->clks[2].id = "bus_master";
+	res->clks[3].id = "bus_slave";
+	res->clks[4].id = "slave_q2a";
+	res->clks[5].id = "tbu";
+
+	ret = devm_clk_bulk_get(dev, ARRAY_SIZE(res->clks), res->clks);
+	if (ret < 0)
+		return ret;
+
+	res->pipe_clk = devm_clk_get(dev, "pipe");
+	return PTR_ERR_OR_ZERO(res->pipe_clk);
+}
+
+static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
+{
+	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+	struct dw_pcie *pci = pcie->pci;
+	struct device *dev = pci->dev;
+	u32 val;
+	int ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
+	if (ret < 0) {
+		dev_err(dev, "cannot enable regulators\n");
+		return ret;
+	}
+
+	ret = clk_bulk_prepare_enable(ARRAY_SIZE(res->clks), res->clks);
+	if (ret < 0)
+		goto err_disable_regulators;
+
+	ret = reset_control_assert(res->pci_reset);
+	if (ret < 0) {
+		dev_err(dev, "cannot deassert pci reset\n");
+		goto err_disable_clocks;
+	}
+
+	msleep(20);
+
+	ret = reset_control_deassert(res->pci_reset);
+	if (ret < 0) {
+		dev_err(dev, "cannot deassert pci reset\n");
+		goto err_assert_resets;
+	}
+
+	ret = clk_prepare_enable(res->pipe_clk);
+	if (ret) {
+		dev_err(dev, "cannot prepare/enable pipe clock\n");
+		goto err_assert_resets;
+	}
+
+	/* configure PCIe to RC mode */
+	writel(DEVICE_TYPE_RC, pcie->parf + PCIE20_PARF_DEVICE_TYPE);
+
+	/* enable PCIe clocks and resets */
+	val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
+	val &= ~BIT(0);
+	writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
+
+	/* change DBI base address */
+	writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
+
+	/* MAC PHY_POWERDOWN MUX DISABLE  */
+	val = readl(pcie->parf + PCIE20_PARF_SYS_CTRL);
+	val &= ~BIT(29);
+	writel(val, pcie->parf + PCIE20_PARF_SYS_CTRL);
+
+	val = readl(pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
+	val |= BIT(4);
+	writel(val, pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
+
+	if (IS_ENABLED(CONFIG_PCI_MSI)) {
+		val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
+		val |= BIT(31);
+		writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
+	}
+
+	return 0;
+err_assert_resets:
+	reset_control_assert(res->pci_reset);
+err_disable_clocks:
+	clk_bulk_disable_unprepare(ARRAY_SIZE(res->clks), res->clks);
+err_disable_regulators:
+	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
+
+	return ret;
+}
+
+static void qcom_pcie_deinit_2_7_0(struct qcom_pcie *pcie)
+{
+	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+
+	clk_bulk_disable_unprepare(ARRAY_SIZE(res->clks), res->clks);
+	regulator_bulk_disable(ARRAY_SIZE(res->supplies), res->supplies);
+}
+
+static int qcom_pcie_post_init_2_7_0(struct qcom_pcie *pcie)
+{
+	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+
+	return clk_prepare_enable(res->pipe_clk);
+}
+
+static void qcom_pcie_post_deinit_2_7_0(struct qcom_pcie *pcie)
+{
+	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
+
+	clk_disable_unprepare(res->pipe_clk);
+}
+
 static int qcom_pcie_link_up(struct dw_pcie *pci)
 {
 	u16 val = readw(pci->dbi_base + PCIE20_CAP + PCI_EXP_LNKSTA);
@@ -1167,6 +1308,16 @@ static const struct qcom_pcie_ops ops_2_3_3 = {
 	.ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
 };
 
+/* Qcom IP rev.: 2.7.0	Synopsys IP rev.: 4.30a */
+static const struct qcom_pcie_ops ops_2_7_0 = {
+	.get_resources = qcom_pcie_get_resources_2_7_0,
+	.init = qcom_pcie_init_2_7_0,
+	.deinit = qcom_pcie_deinit_2_7_0,
+	.ltssm_enable = qcom_pcie_2_3_2_ltssm_enable,
+	.post_init = qcom_pcie_post_init_2_7_0,
+	.post_deinit = qcom_pcie_post_deinit_2_7_0,
+};
+
 static const struct dw_pcie_ops dw_pcie_ops = {
 	.link_up = qcom_pcie_link_up,
 };
@@ -1282,6 +1433,7 @@ static const struct of_device_id qcom_pcie_match[] = {
 	{ .compatible = "qcom,pcie-ipq8074", .data = &ops_2_3_3 },
 	{ .compatible = "qcom,pcie-ipq4019", .data = &ops_2_4_0 },
 	{ .compatible = "qcom,pcie-qcs404", .data = &ops_2_4_0 },
+	{ .compatible = "qcom,pcie-sdm845", .data = &ops_2_7_0 },
 	{ }
 };
 
-- 
2.23.0

Re: [PATCH v2 2/2] PCI: qcom: Add support for SDM845 PCIe controller

[Philipp Zabel]

Hi Bjorn,

On Fri, 2019-11-01 at 17:27 -0700, Bjorn Andersson wrote:
> The SDM845 has one Gen2 and one Gen3 controller, add support for these.
> 
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> ---
> 
> Changes since v1:
> - Style changes requested by Stan
> - Tested with second PCIe controller as well
> 
>  drivers/pci/controller/dwc/pcie-qcom.c | 152 +++++++++++++++++++++++++
>  1 file changed, 152 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> index 7e581748ee9f..35f4980480bb 100644
> --- a/drivers/pci/controller/dwc/pcie-qcom.c
> +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> @@ -54,6 +54,7 @@
[...]
> +static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
> +{
> +	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
> +	struct dw_pcie *pci = pcie->pci;
> +	struct device *dev = pci->dev;
> +	u32 val;
> +	int ret;
> +
> +	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
> +	if (ret < 0) {
> +		dev_err(dev, "cannot enable regulators\n");
> +		return ret;
> +	}
> +
> +	ret = clk_bulk_prepare_enable(ARRAY_SIZE(res->clks), res->clks);
> +	if (ret < 0)
> +		goto err_disable_regulators;
> +
> +	ret = reset_control_assert(res->pci_reset);
> +	if (ret < 0) {
> +		dev_err(dev, "cannot deassert pci reset\n");
> +		goto err_disable_clocks;
> +	}

If for any of the above fails, the reset line is left in its default
state, presumably unasserted. Is there a reason to assert and keep it
asserted if enabling the clocks fails below?

> +	msleep(20);
> +
> +	ret = reset_control_deassert(res->pci_reset);
> +	if (ret < 0) {
> +		dev_err(dev, "cannot deassert pci reset\n");
> +		goto err_assert_resets;

Nitpick: this seems superfluous since the reset line was just asserted
20 ms before. Maybe just:

		goto err_disable_clocks;

> +	}
> +
> +	ret = clk_prepare_enable(res->pipe_clk);
> +	if (ret) {
> +		dev_err(dev, "cannot prepare/enable pipe clock\n");
> +		goto err_assert_resets;
> +	}
> +
> +	/* configure PCIe to RC mode */
> +	writel(DEVICE_TYPE_RC, pcie->parf + PCIE20_PARF_DEVICE_TYPE);
> +
> +	/* enable PCIe clocks and resets */
> +	val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
> +	val &= ~BIT(0);
> +	writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
> +
> +	/* change DBI base address */
> +	writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
> +
> +	/* MAC PHY_POWERDOWN MUX DISABLE  */
> +	val = readl(pcie->parf + PCIE20_PARF_SYS_CTRL);
> +	val &= ~BIT(29);
> +	writel(val, pcie->parf + PCIE20_PARF_SYS_CTRL);
> +
> +	val = readl(pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
> +	val |= BIT(4);
> +	writel(val, pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
> +
> +	if (IS_ENABLED(CONFIG_PCI_MSI)) {
> +		val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
> +		val |= BIT(31);
> +		writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
> +	}
> +
> +	return 0;
> +err_assert_resets:
> +	reset_control_assert(res->pci_reset);

So maybe this can just be removed. The reset isn't asserted in deinit
either.

regards
Philipp

Re: [PATCH v2 2/2] PCI: qcom: Add support for SDM845 PCIe controller

[Bjorn Andersson]

On Mon 04 Nov 01:41 PST 2019, Philipp Zabel wrote:

> Hi Bjorn,
> 
> On Fri, 2019-11-01 at 17:27 -0700, Bjorn Andersson wrote:
> > The SDM845 has one Gen2 and one Gen3 controller, add support for these.
> > 
> > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
> > ---
> > 
> > Changes since v1:
> > - Style changes requested by Stan
> > - Tested with second PCIe controller as well
> > 
> >  drivers/pci/controller/dwc/pcie-qcom.c | 152 +++++++++++++++++++++++++
> >  1 file changed, 152 insertions(+)
> > 
> > diff --git a/drivers/pci/controller/dwc/pcie-qcom.c b/drivers/pci/controller/dwc/pcie-qcom.c
> > index 7e581748ee9f..35f4980480bb 100644
> > --- a/drivers/pci/controller/dwc/pcie-qcom.c
> > +++ b/drivers/pci/controller/dwc/pcie-qcom.c
> > @@ -54,6 +54,7 @@
> [...]
> > +static int qcom_pcie_init_2_7_0(struct qcom_pcie *pcie)
> > +{
> > +	struct qcom_pcie_resources_2_7_0 *res = &pcie->res.v2_7_0;
> > +	struct dw_pcie *pci = pcie->pci;
> > +	struct device *dev = pci->dev;
> > +	u32 val;
> > +	int ret;
> > +
> > +	ret = regulator_bulk_enable(ARRAY_SIZE(res->supplies), res->supplies);
> > +	if (ret < 0) {
> > +		dev_err(dev, "cannot enable regulators\n");
> > +		return ret;
> > +	}
> > +
> > +	ret = clk_bulk_prepare_enable(ARRAY_SIZE(res->clks), res->clks);
> > +	if (ret < 0)
> > +		goto err_disable_regulators;
> > +
> > +	ret = reset_control_assert(res->pci_reset);
> > +	if (ret < 0) {
> > +		dev_err(dev, "cannot deassert pci reset\n");
> > +		goto err_disable_clocks;
> > +	}
> 
> If for any of the above fails, the reset line is left in its default
> state, presumably unasserted. Is there a reason to assert and keep it
> asserted if enabling the clocks fails below?
> 

No, I don't think there's any reason for doing this and looking at the
downstream driver, they don't even propagate this error.

> > +	msleep(20);

And I see now that downstream has this as 1ms, will update and retest
again.

> > +
> > +	ret = reset_control_deassert(res->pci_reset);
> > +	if (ret < 0) {
> > +		dev_err(dev, "cannot deassert pci reset\n");
> > +		goto err_assert_resets;
> 
> Nitpick: this seems superfluous since the reset line was just asserted
> 20 ms before. Maybe just:
> 
> 		goto err_disable_clocks;

Yes, this seems reasonable.

> 
> > +	}
> > +
> > +	ret = clk_prepare_enable(res->pipe_clk);
> > +	if (ret) {
> > +		dev_err(dev, "cannot prepare/enable pipe clock\n");
> > +		goto err_assert_resets;
> > +	}
> > +
> > +	/* configure PCIe to RC mode */
> > +	writel(DEVICE_TYPE_RC, pcie->parf + PCIE20_PARF_DEVICE_TYPE);
> > +
> > +	/* enable PCIe clocks and resets */
> > +	val = readl(pcie->parf + PCIE20_PARF_PHY_CTRL);
> > +	val &= ~BIT(0);
> > +	writel(val, pcie->parf + PCIE20_PARF_PHY_CTRL);
> > +
> > +	/* change DBI base address */
> > +	writel(0, pcie->parf + PCIE20_PARF_DBI_BASE_ADDR);
> > +
> > +	/* MAC PHY_POWERDOWN MUX DISABLE  */
> > +	val = readl(pcie->parf + PCIE20_PARF_SYS_CTRL);
> > +	val &= ~BIT(29);
> > +	writel(val, pcie->parf + PCIE20_PARF_SYS_CTRL);
> > +
> > +	val = readl(pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
> > +	val |= BIT(4);
> > +	writel(val, pcie->parf + PCIE20_PARF_MHI_CLOCK_RESET_CTRL);
> > +
> > +	if (IS_ENABLED(CONFIG_PCI_MSI)) {
> > +		val = readl(pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
> > +		val |= BIT(31);
> > +		writel(val, pcie->parf + PCIE20_PARF_AXI_MSTR_WR_ADDR_HALT);
> > +	}
> > +
> > +	return 0;
> > +err_assert_resets:
> > +	reset_control_assert(res->pci_reset);
> 
> So maybe this can just be removed. The reset isn't asserted in deinit
> either.
> 

Sounds good.

Thanks for your review, Philipp!

Regards,
Bjorn

Re: [PATCH v2 0/2] PCI: qcom: Add support for SDM845 PCIe

[Vinod Koul]

On 01-11-19, 17:27, Bjorn Andersson wrote:
> This second iteration of the patch series fixes review comments on v1 and has
> been tested with both PCIe controllers found on the Qualcomm SDM845.

Reviewed-by: Vinod Koul <vkoul@kernel.org>

-- 
~Vinod